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The construction of in vitro capillary network models for drug testing and toxicity evaluation has become a major challenge in the field of tissue engineering. Previously, we discovered a novel phenomenon of hole formation by endothelial cell migration on the surface of fibrin gels. Interestingly, the hole characteristics, such as depth and number, were strongly influenced by the gel stiffness, but the details of hole formation are not to be clarified. In this study, we tried to understand the effect of hydrogel stiffness on the hole formation by dropping collagenase solution onto the surface of the hydrogels because the endothelial cell migration was made possible by the metalloproteinases' digestion. We found that smaller hole structures were formed on stiffer fibrin gels, but larger ones were formed on softer fibrin gels after the hydrogel digestion of the collagenase. This is consistent with our previous results in experiments on hole structures formed by endothelial cells. Furthermore, deep and small hole structures were successfully obtained by optimizing the volume of collagenase solution and incubation time. This unique approach inspired by endothelial cell hole formation may provide new methods of fabricating hydrogels with opening hole structures. [Display omitted] • The influence of collagenase volume and incubation time on fibrin gel was confirmed. • Collagenase diffusing in hard hydrogel was simulated by FITC-dextran. • A penetrating hole structure on fibrin gel was successfully obtained, inspired by cell behavior. [ABSTRACT FROM AUTHOR]

• Phosphonate-containing mesoporous silica spheres were synthesized. • The synthesis of the spheres was achieved under the basic condition. • The BET surface area of the particle decreased with adding phosphonate. • Phosphonate would occur the morphological changes of the sphere. • The particles with the hollow structures were observed by a TEM. Phosphonate-containing mesoporous silica (PMPS) spheres were successfully synthesized using diethyl(2-bromoethyl)phosphonate and non-ionic and cationic surfactants. The spherical PMPS particles with the mesopores were effectively formed under the basic condition through the hydrolysis and condensation reactions of tetraethoxysilane, even though the BET surface area of the particles decreased with increasing the added phosphonate amount. The hollow structures with the mesopores were obtained in the preferential amount of the phosphonate. [ABSTRACT FROM AUTHOR]

Accurate recognition of disabled persons' behavioral intentions is the key to reconstructing hand function. Their intentions can be understood to some extent by electromyography (EMG), electroencephalogram (EEG), and arm movements, but they are not reliable enough to be generally accepted. In this paper, characteristics of foot contact force signals are investigated, and a method of expressing grasping intentions based on hallux (big toe) touch sense is proposed. First, force signals acquisition methods and devices are investigated and designed. By analyzing characteristics of signals in different areas of the foot, the hallux is selected. The peak number and other characteristic parameters are used to characterize signals, which can significantly express grasping intentions. Second, considering complex and fine tasks of the assistive hand, a posture control method is proposed. Based on this, many human-in-the-loop experiments are conducted using human–computer interaction methods. The results showed that people with hand disabilities could accurately express their grasping intentions through their toes, and could accurately grasp objects of different sizes, shapes, and hardness using their feet. The accuracy of the action completion for single-handed and double-handed disabled individuals was 99% and 98%, respectively. This proves that the method of using toe tactile sensation for assisting disabled individuals in hand control can help them complete daily fine motor activities. The method is easily acceptable in terms of reliability, unobtrusiveness, and aesthetics. [ABSTRACT FROM AUTHOR]

The combination of sticky rice pulp and tabia is a building material in ancient China, while the concrete preparation with sticky rice pulp instead of water is a new concept, and exploratory experimental study on its working and mechanical properties is indispensable. Therefore, on the basis of concrete substrates of Chinese C25, sticky rice pulp with different concentrations was used to replace water to complete the preparation of concrete, and its slump and compressive strength test under different ages was carried out. The results showed that sticky rice pulp could be a retarder and reduce the water‐cement ratio to a certain extent, and amylopectin in sticky rice pulp could also play the role of template. In addition, there is cementation of coarse and fine aggregate by adhesive components in sticky rice pulp. These effects cause the compressive strength of concrete to decrease at the early stage and increase at the later stage, and in terms of strength alone, the optimal concentration of sticky rice pulp that replaces water is about 1%. According to the test results, the influence functions of cube compressive strength of concrete with sticky rice pulp at 3d and 28d ages, as well as the correlation function of cube compressive strength and two variables about concentration and age of sticky rice pulp were also fitted. The results of the above series of exploration provide basis for the engineering application of concrete with sticky rice pulp in future, which is an environmentally friendly building material. [ABSTRACT FROM AUTHOR]

[Display omitted] • Firstly, the local linear model established in this paper presents the gradient information of the VIS image as the pixel intensity of the IR image. • Secondly, the detail perception factor and contrast control factor are introduced into the design of the cost function, which has the effect of enhancing contrast and suppressing noise moderately • Finally, this paper adopts the strategy of dual-scale decomposition to obtain infrared features and combine them with the initial fusion results. This scheme enriches the detailed texture information from the IR image in the fusion result. Infrared (IR) and visible (VIS) images represent the features of the scene at different wavelengths, and the features they contain have different properties. Therefore, the traditional weighted fusion strategy is challenging to preserve the different types of feature information. In addition, VIS images are highly susceptible to bad weather, which also seriously affects the quality of fused images in complex environments. To solve the above problems, we propose a feature enhancement fusion method. First, a fusion model called contrast enhancement guided filter (CEGF) is proposed. The new model enables the texture information of VIS images to be presented with the intensity of infrared pixels, which solves the problem of combining different attribute features and removes the influence of harsh lighting conditions. To improve the visibility of texture details under different lighting conditions, a contrast modulation factor is added to the cost function design of the filter to enhance the contrast of visible details. Second, we use a dual-scale decomposition strategy to enhance the infrared feature information of the fusion results. Finally, we apply the method of this paper with ten classical image fusion algorithms in two types of datasets. The visual effect and objective evaluation of the fusion results verify that the proposed method preserves the characteristics of the high contrast of IR images and improves the visibility of infrared scenes for subsequent target identification and detection. [ABSTRACT FROM AUTHOR]

In order to improve the spatial resolution of an optical micro-scanning thermal microscope system, the micro-scanning position must be accurately calibrated. An adaptive calibration method based on image registration and plane coordinate system is proposed. The meaning of calibration is given, and the principle and method of point calibration are introduced in detail and experiments using the real system were done. Different reconstruction methods were applied to reconstruct the visible light image and the real thermal microscope image, and the evaluation scores are given. Results of simulation and real thermal imaging processing show that the method can successfully calibrate the micro-scanning position. The method can significantly improve the oversampled reconstructed image quality, thus enhancing the spatial resolution of the system. This method can also be used in other electro-optical imaging systems. [ABSTRACT FROM AUTHOR]